“Do you collect bonus points?” This question is part of daily purchasing routine. More than 80% of German households participate in bonus programs. They run the risk of disclosing sensitive information about themselves, if such a system is misused. For this reason, the Cryptography and Security Group of Karlsruhe Institute of Technology (KIT) develops a digital bonus and payment system that protects anonymity of clients, but also offers the added values desired by operators.